Core yarn, and method and device for manufacturing the same

ABSTRACT

Automation of a manufacturing device for a core yarn that an elastic yarn that is a core fiber becomes high stretchy, the yarn strength of the core yarn as a single yarn is high and a fiber comprising a fiber bundle is wrapped around the elastic yarn that is the core fiber. Regarding a core yarn  12  that the fiber bundle made from the cotton 100% covers an elastic yarn  11  used as the core fiber, the elastic yarn  11  used as the core fiber is drafted in more than 4 times of the drafting magnification between an elastic yarn supply device  10  and a yarn delivering device  14  disposed in the downstream side of a spinning device  13  for implementing air spinning by the vortex air current and having an air spinning nozzle  86  for generating the vortex air current and a hollow guide shaft  80  and a fiber bundle  5  covers the core fiber by centralizing the elastic yarn  11.

FIELD OF THE INVENTION

[0001] The present invention relates to a core yarn in the state that fibers comprising a fiber bundle made from the cotton is wrapped around an elastic yarn used as a core fiber by the air spinning using vortex air current and a covering of the fiber to the elastic yarn is improved, and more particularly to a method of manufacturing the same. More specifically, the yarn strength of the core yarn used as a single yarn becomes higher when spinning the elastic yarn that is the core fiber by making it higher stretch than usual and the cost for manufacturing a spun yarn can be reduced. Besides, the present invention relates to a technique for automating a manufacturing device to produce the core yarn in the state that the fiber comprising the fiber bundle is wrapped around the elastic yarn used as the core fiber.

BACKGROUND OF THE INVENTION

[0002] The applicant has already made an application for the technique in the Japanese Patent No. 2734805, regarding the core yarn manufacturing device that an air spinning device is improved upon and the elastic yarn is used as the core fiber and the fiber bundle is used as the covering fiber.

[0003] A staple fiber and a blended sliver of the staple fiber and the cotton have been used as the covering fiber in such a conventional core yarn manufacturing device. Alternatively, a cotton 100% short fiber is sometimes used as the covering fiber for softening clothes.

[0004] Moreover, when producing the core yarn by using the conventional ring spinning machine etc., the core yarn is manufactured in the spinning speed of about 20 meters/minute.

[0005] Conventionally, the air spinning technique for realizing the high speed spinning whose speed is about ten times of the one by the ring spinning machine is publicly known for speeding up the spinning speed. The techniques in the Japanese patent No. 2734805 and No. 2862107 are publicly known as the core yarn manufacturing device for manufacturing the core yarn whose core fiber is the elastic yarn in such an air spinning device.

[0006] Meanwhile, if the elastic yarn is used as the core fiber and the (for example, cotton 100%) short fiber is used as the covering fiber when using the above ring spinning machine, the core yarn wherein the twist is extended to even an elastic yarn 11 is produced as illustrated in FIG. 6.

[0007] Regarding the core yarn as illustrated in FIG. 6, the elastic yarn 11 that is the core fiber and a covering fiber bundle 5 are not coherent and intertwisting and a part of the elastic yarn 11 comes out between the covering fibers 5. Accordingly, there was a problem in the covering of the fiber bundle 5 for wrapping around the elastic yarn 11.

[0008] Consequently, as a piece of core yarn is produced in the state that the elastic yarn and the fiber bundle are easy to separate, it transpires that the elastic yarn is bared since the surrounding fiber bundle is slipped on the elastic yarn to break if this single yarn is pulled strongly to the longitudinal direction. More specifically, as the fiber bundle is slipped on the elastic yarn when the core yarn is pulled to the longitudinal direction, the power necessary for breaking the fiber bundle becomes weak (the durability to the friction is low). Further, the power necessary for breaking the whole core yarn without the fiber bundle slipping on the elastic yarn (the single yarn strength that is the ultimate tensile strength) depends only on the strength of the outer fiber bundle, and the strength of the elastic yarn used as the core fiber turns out not to affect the whole strength.

[0009] Moreover, as the device described in the Japanese patent No. 2734805 in the core yarn manufacturing device using the elastic yarn concerning the above conventional spinning technique threads the elastic yarn into the air spinning nozzle manually, the operation cannot be restarted by piecing the spinning side core yarn and the winding side core yarn automatically once the operation is stopped for some reason. More specifically, every time the cutter breaks the yarn when generating the slub, the operator has to supply the elastic yarn manually.

[0010] The structure that the elastic yarn is automatically supplied from the upstream side of the front roller of the drafting unit is concretely disclosed in the Japanese patent No. 2862107. However, the other movement in piecing (the movement except the supplying movement of the elastic yarn) is not completely disclosed. More specifically, the relation between the timings for starting to supply the sliver and the elastic yarn is not definitely described in the Japanese patent No. 2862107.

[0011] In this case, if the elastic yarn is supplied in the state that the sliver is not running properly in piecing for example, there is a possibility that the elastic yarn is jammed in the spinning nozzle. The operation cannot be restarted automatically when such a situation is happened. Moreover, when only the elastic yarn is supplied and introduced into the yarn piecing device in the state of failing to discharge the yarn (the spun yarn is produced and discharged from the sliver) when starting the spinning, the problem is also happened that only the elastic yarn is wound to the package sequentially.

[0012] It is an object of the present invention to solve the problem that the fiber bundle and the elastic yarn in the conventional core yarn are easily slipped and separated, and to get the soft core yarn with high single yarn strength, high durability to the friction and strong cohesion of the elastic yarn and the fiber bundle, with the structure that the elastic yarn with no twist is collected to the center and the cotton short fiber is wrapped and covered around it.

[0013] Moreover, the core yarn whose yarn strength is high can be manufactured at high speed by the core yarn manufacturing method that the nozzle for generating the vortex air current and the hollow guide shaft are provided and the air spinning is implemented by the vortex air current.

[0014] Further, regarding the core yarn, a part of the covered cotton fiber bundle is wrapped around the periphery of the elastic yarn that is the core fiber in the middle of the fiber so as to adhere to each other more.

[0015] It is another object of the present invention that the yarn piecing and the restart of the operation can be implemented without the burden of the operator by surely delivering the core yarn including the elastic yarn if the yarn is broken when generating the slub in the core yarn manufacturing device.

SUMMARY OF THE INVENTION

[0016] The problems to be solved by the prevent invention are described above, and next, the means for solving the problems will be described.

[0017] In claim 1, the core yarn, that the fiber bundle made from the short fiber is covered around the elastic yarn used as the core fiber, is characterized in that the power necessary for breaking the fiber bundle after slipping on the elastic yarn in pulling to the longitudinal direction is stronger than the power necessary for breaking the whole yarn in pulling to the longitudinal direction.

[0018] In claim 2, the core yarn, that the fiber bundle made from the short fiber is covered around the elastic yarn used as the core fiber, is characterized in that the covering of the fiber bundle around the elastic yarn that is the core fiber by collecting to the center has a fascinated part that a part of the fiber bundle is wrapped around the elastic yarn.

[0019] In claim 3, the core yarn, that the fiber bundle made from the short fiber is covered around the elastic yarn used as the core fiber, is characterized in that the fiber bundle is covered around the core fiber by drafting the elastic yarn used as the core fiber in the drafting magnification of more than 4 times between the elastic yarn supply device and the yarn delivering device disposed in the downstream side of the spinning device which is equipped with the air spinning nozzle for generating the vortex air current and the hollow guide shaft for implementing air spinning by the vortex air current and centralizing the elastic yarn.

[0020] In claim 4, the core yarn that the fiber bundle made from the short fiber is covered around the elastic yarn used as the core fiber, is characterized in that the elastic yarn is disposed in parallel to the longitudinal direction in the central part of the core yarn and one end of each fiber comprising the fiber bundle of the covering is located in the central part of the core yarn with turning to the longitudinal direction in almost parallel and the other end is exposed in the outer surface of the core yarn spirally, and the fiber bundle of the covering has the consecutive structure that the other end of each fiber is wrapped around the other trailing fiber and the other end of the other fiber is wrapped around the more other trailing fiber.

[0021] In claim 5, the core yarn manufacturing method is characterized in providing the elastic yarn supply device and the spinning device implementing the air spinning by the vortex air current equipped with the air spinning nozzle for generating the vortex air current and the hollow guide shaft, wherein the fiber made by the short fiber comprising the fiber bundle is covered by the elastic yarn used as the core fiber which is drafted in the drafting magnification of more than 4 times between the elastic yarn supply device and the yarn delivering device disposed in the downstream side of the spinning device and that the elastic yarn and the fiber bundle are supplied to the hollow guide shaft by the spinning device at the same time of drafting.

[0022] In claim 6, the core yarn manufacturing device, having the drafting unit for drafting the fiber bundle, the elastic yarn supply device for supplying the elastic yarn used as the core fiber to the fiber bundle, the air spinning device for producing the core yarn by introducing the elastic yarn and the fiber bundle and activating the vortex air current, the yarn delivering device disposed in the downstream side of the air spinning device, the winding device for winding the core yarn discharged from the yarn delivering device and the yarn piecing device for piecing the spinning side core yarn to the winding side core yarn, is equipped with the drafting unit for introducing the yarn discharged from the air spinning device to the piecing device, the detector for detecting the yarn presence in the drafting unit and the control unit for controlling the supply of the elastic yarn by the elastic yarn supply device based on the result of the detector.

[0023] In claim 7, the core yarn manufacturing device, having the drafting unit for drafting the fiber bundle, the elastic yarn supply device for supplying the elastic yarn used as the core fiber to the fiber bundle, the air spinning device for producing the core yarn by introducing the elastic yarn and the fiber bundle and activating the vortex air current, the yarn delivering device disposed in the downstream side of the air spinning device, the winding device for winding the core yarn discharged from the yarn delivering device and the yarn piecing device for piecing the core yarn in the spinning side to the core yarn in the winding side, is equipped with the drafting unit for introducing the yarn discharged from the air spinning device to the yarn piecing device by drafting it, the detector for detecting that the delivering power by the yarn delivering device is applied to the yarn drafted by the drafting unit and the control unit for controlling the supply of the elastic yarn by the elastic yarn supply device based on the result of the detector.

[0024] In claim 8, the drafting unit is the movable suction tube, and the detecting part detects the spun yarn presence in the suction path of the suction tube.

[0025] In claim 9, the elastic yarn supply device is equipped with the air sucker device and the clamp cutter device, and the control unit controls to release the clamp of the elastic yarn by the clamp cutter device after the predetermined time has passed since the air sucker device is activated in starting to supply the elastic yarn.

[0026] In claim 10, the elastic yarn supply device is equipped with a rotating supply roller in contact with a yarn feeding body of the elastic yarn, and the control unit controls to start the supply of the elastic yarn by the supply roller at almost the same time of releasing the clamp of the elastic yarn by the clamp cutter in starting to supply the elastic yarn.

[0027] In claim 11, the air spinning device, equipped with the hollow guide shaft and the nozzle member for generating the vortex air current in the tip part of the hollow guide shaft, produces the core yarn by activating the vortex air current by the nozzle with supplying the elastic yarn and the fiber bundle from the tip side to the yarn path of the hollow guide shaft.

BRIEF DESCRIPTION OF THE DRAWINGS

[0028]FIG. 1 is a front view illustrating the spinning device and the yarn piecing vehicle for the core yarn of the present invention.

[0029]FIG. 2 is an enlarged sectional side view of the part of the spinning device and the yarn piecing vehicle in FIG. 1.

[0030]FIG. 3 is an enlarged side view of the part of the spinning part, the suction nozzle and the yarn piecing vehicle.

[0031]FIG. 4 is a bird's eye view illustrating the spinning part, the suction nozzle and the substantial part of the present invention.

[0032]FIG. 5 is an enlarged view of the core yarn of the present invention.

[0033]FIG. 6 is an enlarged view of the conventional core yarn.

[0034]FIG. 7 is a perspective view illustrating the appearance of the wrapping of the covering fiber.

[0035]FIG. 8 is a control block diagram of the core yarn spinning device of the present invention.

[0036]FIG. 9 is a timing chart of the core yarn spinning device of the present invention.

[0037]FIG. 10 is a diagram illustrating the characteristic of the drafting magnification and the yarn strength of the elastic yarn that is the core fiber in the core yarn generated by the ring spinning machine, the core yarn manufactured by the conventional spinning method and device using the staple fiber as the covering fiber and the core yarn manufactured by the manufacturing method of the present invention using the cotton 100% covering fiber.

[0038]FIG. 11 is a bird's eye view illustrating the substantial part in the preferred embodiment of the present invention, wherein the supply part of the core fiber is motor driven.

[0039]FIG. 12 is a sectional view of the air spinning device with the hollow guide shaft.

[0040]FIG. 13 is a sectional view illustrating the behavior of the fiber bundle in the spinning by the air spinning device.

[0041]FIG. 14 is an enlarged sectional view illustrating the detail of the hollow guide shaft.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0042] Next, the preferred embodiment of the present invention will be described. First, the total structure of the core yarn manufacturing device will be described with reference to FIG. 1˜FIG. 4.

[0043] The core yarn manufacturing device is composed by setting out a plurality of spinning units 1 to the longitudinal direction of the machine. A drafting unit 6 is provided in the upper part of the respective spinning units 1. The drafting unit 6 drafts a sliver 4 which is provided from a sliver can 2 in the back part through a guide 3 and becomes the covering of the core yarn, and doubles to a predetermined fiber bundle 5 as illustrated in FIG. 2. Additionally, the sliver 4 composed by the cotton 100% short fiber is used as the raw material in the preferred embodiment of the present invention, but the raw material is not confined to this.

[0044] The drafting unit 6 is mainly composed by a back roller 7, a middle roller 8 wound to the apron and a front roller 9 as illustrated in FIG. 3. An air spinning device 13 is disposed in the downstream side of this drafting unit 6, close to the front roller 9. A clutch (reference number 75 illustrated in FIG. 8) transmitting the power to the back roller 7 intermittently is connected to a control unit 51 and the transmission/interruption of the power is controlled by the control unit 51.

[0045] The respective spinning units 1 is equipped with an elastic yarn supply device 10 for supplying an elastic yarn 11 whose elasticity is higher to a fiber bundle 5 (the sliver 4) in the drafting unit 6.

[0046] The air spinning device 13 spins the elastic yarn 11 supplied from the elastic yarn supply device 10 and the fiber bundle 5 drafted by the drafting unit 6 by activating the vortex air current of the compressed air from an air spinning nozzle 86 and manufactures a core yarn 12 whose outside is covered by the fiber of the fiber bundle 5, using the elastic yarn 11 as the core fiber.

[0047] A suction flow generating nozzle 82 for discharging yarn is annexed other than the air spinning nozzle 86 in the air spinning device 13 (mentioned later) , and it is composed such that the fiber bundle 5 is discharged as the spun yarn having the predetermined strength from the outlet of the air spinning device 13 after being introduced to the yarn path automatically and spun in the air spinning device 13 when the fiber bundle 5 is discharged from the drafting unit 6 and the spinning is started.

[0048] Regarding the covering of the fiber bundle 5 described before, the core yarn 12 manufactured by the core yarn manufacturing device of the present invention is composed by wrapping around the elastic yarn 11 spirally as illustrated in FIG. 5A and is additionally composed by wrapping the fiber bundle 5 and the elastic yarn 11 by composing a fascinated part K at the predetermined interval on the periphery of the single yarn.

[0049] A yarn delivering device 14 is provided as the yarn delivering device for feeding the manufactured core yarn 12 to the downstream side by applying the delivering power in the downstream of the air spinning device 13.

[0050] As illustrated in FIG. 2˜FIG. 4, the yarn delivering device 14 is composed by a pair of rollers that are the constantly rotating delivery roller in the downstream side and a nip roller in the upper side which is rotated by contacting with the delivery roller, and the delivering power is applied to the yarn by nipping the yarn between both rotating rollers.

[0051] A winding unit 16 for winding the core yarn 12 fed from the yarn delivering device 14 to a package 15 is provided in the lower part of the front surface of the unit 1.

[0052] Moreover, as illustrated in FIG. 4, a slub catcher (yarn defective detector) 17 for detecting the yarn defect such as the yarn unevenness of the feeding core yarn 12 is provided between the yarn delivering device 14 and the winding unit 16, and the control unit 51 activates a cutter 63 (FIG. 4) provided in the downstream side of the yarn delivering device 14 and controls to cut the core yarn 12 by the signal from the slub catcher 17 accompanied by detecting this yarn defect.

[0053] In the present invention, as the clutch (reference number 75 in FIG. 8) is pushed down with cutting the yarn by the cutter 63 by the control of the control unit 51, the drive of the back roller 7 composing the drafting unit 6 is stopped, the spinning of the core yarn is stopped by stopping the air spinning device 13 and the drive of an elastic yarn package 20 described later is also stopped.

[0054] Moreover, a clamp cutter device 33 (FIG. 4) composing the elastic yarn supply device 10 is stopped in the state that the tip of the end part of the elastic yarn 11 is clamped and cut by switching an electromagnetic control valve 56.

[0055] An actuator 54 controls the clamp cutter device 33 and the electromagnetic control valve 56 for controlling the high pressure air supplied to the actuator 54 is provided. The electromagnetic control valve 56 is also opened and closed by the signal from the control unit 51. In addition, the control block diagram of the spinning device of the present invention including the control unit 51 is illustrated in FIG. 8.

[0056] The elastic yarn 11 supplied from the elastic yarn supply device 10 provided over the drafting unit 6 is arranged to merge into the fiber bundle 5 in between the front roller 9 and the middle roller 8, to pass the front roller 9 with the fiber bundle 5 and to introduce to the air spinning device 13.

[0057] As illustrated in FIG. 1, this elastic yarn supply device 10 has a common drive spindle 19 which is passed along the spinning unit 1 which is set out and is rotation driven by one motor 18, and a rotating roller (an elastic yarn discharging roller) 21 driving the package 20 (the supply yarn winding body) of the elastic yarn 11 is installed in the respective spinning units 1 in the drive spindle 19.

[0058] The package 20 of the elastic yarn 11 is rotatably supported by a cradle arm 23 installed elevatably to the horizontal axis 22. The elastic yarn package 20 is contacted on the rotating roller 21 and is arranged to be affected by the rotation. As illustrated in FIG. 4, a stopper 24 for stopping the rotation of the package 20 in breaking the core yarn 12 can be inserted freely in between the rotating roller 21 and the elastic yarn package 20.

[0059] More precisely, as illustrated in FIG. 4, the shaft of the stopper 24 is rotatably supported by the axis, and the stopper 24 is arranged so that the tip part can be freely inserted in between the rotating roller 21 and the elastic yarn package 20 by the rotation. The stopper 24 is not contacted with the rotating roller 21, and is inserted between the rotating roller 21 and the package 20.

[0060] An actuator 29 is connected to the stopper 24, and the actuator 29 is kept in the state that the stopper 24 is getting out of the rotating roller 21 and the package 20 regularly and the rotation of the elastic yarn package 20 is arranged to be stopped by inserting the stopper 24 between the rotating roller 21 and the package 20 based on the signal from the stub catcher 17. As illustrated in FIG. 8, this actuator 29 is controlled by the control unit 51 through a cradle electromagnetic control valve 50.

[0061] First, when starting the spinning by operating the core yarn manufacturing device for the first time, the elastic yarn 11 released from the package 20 is sucked into a funnel part 60 composing the elastic yarn supply device 10 by the manual operation of the operator, passes an air sucker device 58 for air threading, an elastic yarn detecting sensor 32 and the clamp cutter device 33 and is supplied from an elastic yarn supply guide tube 59 to the front position of the front roller 9.

[0062] The part of the funnel part 60, the air sucker device 58 for air threading, the clamp cutter device 33 and the elastic yarn supply guide tube 59 is totally stored in a turn box 52 integrally, for an elastic yarn supply guide tube 59 can be evacuated by turning right and left in order not to interfere with the lifting in case that the half of the upper part of the above drafting unit 6 is lifted by operating a lifting handle 53, for the purpose that the sliver 4 is nipped by the drafting unit 6 after the check and fix is implemented in a first step of the spinning.

[0063] As illustrated in FIG. 2, a frame body la of the unit 1 in the core yarn manufacturing device is formed C-shaped whose front is open, wherein rails 37, 38 are laid in the inner space consecutive to the longitudinal direction and the yarn piecing vehicle 39 is disposed which can freely run along the rails 37, 38.

[0064] A suction nozzle 41 that is the suction tube turnable to up and down and a turnable suction mouth 42 are provided in this yarn piecing vehicle 39. The suction nozzle (the extruding device) 41 sucks the yarn end in the spinning side of the air spinning device 13 by turning to the upper direction from a yarn guide position A illustrated in FIG. 2 that the suction mouth is located lower than a yarn piecing part 40 to the position that the suction mouth is in the vicinity of the outlet of the air spinning device 13 (the yarn capturing position) as illustrated by the alternate long and two short dashes line in FIG. 2, and next, it is returned to the yarn guide position A for the yarn end to guide to the yarn piecing part 40.

[0065] Moreover, the suction mouth 42 pulls up the yarn end which is delivered by reversing a winding package 15 held in the lower winding unit 16 by turning to a waiting position B (FIG. 2) for introducing to the yarn piecing part 40.

[0066] Moreover, the yarn piecing vehicle 39 has a cam 43 for driving the suction nozzle 41 and the suction mouth 42, a cam motor M for driving the cam 43 and a blower for generating the suction power etc.

[0067] The yarn piecing vehicle 39 has a nozzle detecting sensor 44 for detecting the movement of the suction nozzle 41 from the waiting position (the yarn guide position) A to the yarn capturing position that the mouth of the suction nozzle 41 is located in the vicinity of the outlet of the air spinning device 13 and a 1-cycle termination detecting sensor 45 for detecting one rotation of the cam 43.

[0068] Additionally, it is arranged to complete the movement that the suction mouth 42 pulls up the winding unit 16 side yarn end and the movement of the suction nozzle 41 that the air spinning device 13 side yarn end is pulled to the yarn piecing part 40 during one rotation of the cam 43.

[0069] The suction nozzle 41 is the suction tube which is composed freely movable to any direction, but the preferred embodiment of the present invention uses the freely turnable suction nozzle 41 not only to up and down direction as an example. A sensor 66 in the suction nozzle illustrated in FIG. 4 plays a role as the detecting part for detecting the yarn presence in the suction route of the suction nozzle 41. The control unit (hereinafter referred to as “vehicle side control unit”), provided in the yarn piecing vehicle 39 side, controls the cam motor M based on the detecting result of the sensor 66 in the suction nozzle 41. The control unit 51 in the spinning unit 1 side can communicate with the vehicle side control unit by the signal using the signal communication means not shown in the drawings. This signal communication means can be replaced by the non-contact communication means.

[0070] Next, when the suction nozzle 41, that is the suction tube, is turned down, the yarn sucked into the suction nozzle 41 along with the turn is entered in between the nip roller and the delivery roller of the yarn delivering device 14 and is applied the delivering power by being nipped by the both rollers. When the sensor 66 in the suction nozzle 41 detects the yarn presence in this state, the (incomplete) spun yarn by only the fiber bundle 5 is discharged smoothly from the air spinning device 13 by the air jet of an after-mentioned suction flow generating nozzle 82 and it determines that the delivering power is applied to the yarn by the yarn delivering device 14.

[0071] Next, as the control unit 51 controls to start the supply of the elastic yarn 11 from the elastic yarn supply device 10 based on the above determination, the supply of the complete core yarn is started that the elastic yarn 11 is included in the fiber bundle 5.

[0072] Next, the structure of the air spinning device 13 and the suction flow generating nozzle 82 for discharging the yarn will be described with reference to FIG. 12˜FIG. 14.

[0073] The air spinning device 13 is composed by a nozzle block (member) B and a hollow guide shaft 80 as illustrated in FIG. 12. The air spinning nozzle 86 that is the nozzle for generating the vortex air current and a fiber introducing hole 83 of a fiber introducing member 84 introducing the fiber bundle 5 are provided in the nozzle block B constituting the air spinning device 13.

[0074] Further, a needle 85 is provide in the nozzle block B. The needle 85, disposed on the same axis as a yarn path 81 of the hollow guide shaft 80, has the functions of guiding the fiber from the fiber introducing hole 83 to the yarn path 81 of the hollow guide shaft 80 and of being easy to turn the fiber inversely in the tip of the hollow guide shaft 80 by blocking the diffusion of the false twisting to the front roller 9 by blocking the balloon. The needle 85 that is the guide member forms the fiber guide space surrounded by a plurality of the members without confining to a piece of the needle shape in the drawing and can be also guided to the yarn path 81 of the hollow guide shaft 80 by passing the fiber discharged from the fiber introducing hole 83 through the fiber guide space.

[0075] The suction flow generating nozzle 82 for discharging yarn is provided in the way of the yarn path 81 consecutively formed from the tip inlet to the outlet in the hollow guide shaft 80 as illustrated in FIG. 14. The nozzle 82 is composed to be able to generate the air current from the tip inlet to the outlet in the yarn path 81 and the fiber can be drawn into the yarn path 81 by the air current.

[0076] The fiber bundle 5 is guided to the yarn path 81 of the hollow guide shaft 80 with wrapping around the core fiber constituting the elastic yarn 11 by receiving the vortex air current generated by the air spinning nozzle 86 in the tip part of the hollow guide shaft 80. Therefore, the core yarn 12 having the elastic yarn 11 in the center is constituted by implementing the spinning generating the truly twisted-like spun yarn.

[0077] More precisely, the fiber bundle 5 and the elastic yarn 11 discharged through the fiber introducing hole 83 is contacted to the needle 85 by being pushed by the vortex air current and is introduced into the hollow guide shaft 80 by being wrapped around the peripheral surface of the needle 85 as illustrated in FIG. 13.

[0078] The tip side of the respective fibers constituting the fiber bundle 5 discharged from the fiber introducing hole 83 is introduced into the hollow guide shaft 80 in the state that the surroundings is wrapped by the respective fibers of the spun yarn which is going to be formed in the vicinity of the tip of the hollow guide shaft 80. On the other hand, after the back end side of the fiber is loosen once by the action of the vortex air current in the spinning room that is the space between the nozzle block B and the hollow guide shaft 80 as illustrated in FIG. 13, it is turned inversely and wrapped around the peripheral surface of the hollow guide shaft 80 spirally. However, right after that, the back end side of the fiber is sucked into the hollow guide shaft 80 with being swung around the fiber bundle 5 heading for the hollow guide shaft 80 by the vortex air current.

[0079] The back end side of the fiber is wrapped around the periphery of the fiber bundle 5 heading into the hollow guide shaft 80 with going around it like this and the truly-twisted-like spun yarn is formed. In this case, the fiber bundle whose back end side of the fiber is wrapped around includes the tip side of the fiber which is newly discharged from the fiber introducing hole 83 and the back end side of the other fiber is also wrapped around the periphery of the fiber bundle 5 with turning around the fiber bundle 5 as described above when closing to the hollow guide shaft 80.

[0080] As the fiber bundle 5 is delivered after wrapping to the needle 85 once though the fiber is turned and twisted by the vortex air current in the spinning room, the spinning can be done in good condition without diffusing the twist of the fiber bundle 5 to the upstream side.

[0081] The suction flow generating nozzle 82 for discharging yarn as illustrated in FIG. 14 can generate the suction flow for sucking the fiber into the yarn path 81 by jetting the compressed air from the nozzle 82.

[0082] The tips of the elastic yarn 11 and the fiber bundle 5 can be sucked into the hollow guide shaft 80 by activating the nozzle 82 in addition to the air spinning nozzle 86 when starting the spinning, and the spun yarn having the predetermined strength (the strength such as not to break if being drawn by the turn of the suction nozzle 41) can be discharged.

[0083] The suction flow generating nozzle 82 for discharging yarn is activated in the predetermined time in restarting the drive of the drafting unit 6 and the air spinning device 13 when the spinning side yarn and the winding side yarn are pieced though it is not jet in the normal spinning, and the yarn discharging spinning for spinning yarn is implemented by generating the jet air with the air spinning nozzle 86 and the suction flow generating nozzle 82 for discharging yarn. The on-off of the suction flow generating nozzle 82 for discharging yarn is controlled by switching a switch valve 76 as illustrated in FIG. 8 by the control unit 51.

[0084] In the present invention, as the suction flow generating nozzle 82 for discharging yarn composed by the hollow guide shaft 80 is provided in the air spinning device 13 part, the yarn can be discharged automatically in restarting the spinning.

[0085] Moreover, the spinning principle that the long fiber is centralized and the short fiber is wrapped around the outside is applicable in the spinning utilizing the air spinning device 13 as described in the present invention. As the short fiber is used as the covering of the fiber bundle 5 in the preferred embodiment of the present invention, the good covering with no twist in the elastic yarn 11 can be acquired as illustrated in FIG. 5.

[0086] When focusing on the winding shape about the respective covering fibers constituting the fiber bundle 5, as illustrated in FIG. 7A, a part of an area 5 x in the tip side of the fiber is placed in almost parallel to the longitudinal direction of the core yarn 12 and is wrapped around the elastic yarn 11 that is the core fiber, but the other area 5 y in the back end side of the fiber is wrapped spirally with getting away from the elastic yarn 11 (the fiber is wrapped around the frustum cone body spirally). The core yarn 12 is produced by that these respective fibers is wrapped around the elastic yarn 11 sequentially as illustrated in FIG. 7B.

[0087] More precisely, the tip side of the fiber 5 a is almost parallel to the longitudinal direction of the core yarn 12 and the back end side of an other fiber 5 b is wrapped around it spirally. The tip side of the other fiber 5 b is also almost parallel to the longitudinal direction of the core yarn 12 and the back end side of a more other fiber 5 c is wrapped around it spirally. Thus, the tip side of the respective fibers 5, 5—is wrapped around the back end side of the other fiber. As the fibers 5 part in the wrapping side becomes the spiral shape part 5 y as described above, when focusing on the fiber structure as illustrated in FIGS. 7A and 7B, the elastic yarn 11 that is the core yarn is disposed in the center and is parallel to the longitudinal direction in the core yarn 12 of the present invention that the fibers 5, 5—are wrapped like this.

[0088] Meanwhile, the tip side of the covering fiber 5 is centralized in the central part of the core yarn with heading to be parallel to the longitudinal direction of the core yarn (the longitudinal direction of the elastic yarn 11) and the back end side is exposed on the outer surface of the core yarn with wrapping spirally. As the core yarn has the consecutive structure such that the back end of the leading-side fiber is wrapped around the just trailing side fiber, for example the back end of one fiber is wrapped to the other consecutive fiber and the back end of the other fiber is wrapped to the more other fiber, high durability to the friction is demonstrated in the direction along the longitudinal direction of the core yarn.

[0089] On the other hand, the core yarn manufactured by the ring spinning machine has the structure that not only the covering fiber but also the core fiber (the elastic yarn) are twisted, the whole covering fiber is twisted spirally regardless of the tip side and the back end side and the respective covering fibers is laid in parallel to the other fiber (along the other fiber). Moreover, the elastic yarn that is the core yarn also has the structure that it is almost parallel to the covering fiber.

[0090] Thus, this structure makes the yarn weak to the friction to the longitudinal direction of the core yarn.

[0091] The core fiber (the elastic yarn 11) is strongly united to the covering fiber (the fiber bundle 5) in the core yarn 12 manufactured by the core yarn manufacturing device of the present invention and the durability to the friction is higher than the single yarn strength (tension breaking strength) of the core yarn 12 as the fiber bundle 5 is strongly united to the elastic yarn 11when the core yarn 12 is pulled to the longitudinal direction of the core yarn 12 (the elastic yarn 11).

[0092] Therefore, the durability to the friction is improved to the extent that the core yarn 12 is broken before the fiber bundle 5 (the covering fiber) is apart from the elastic yarn 11 and the elastic yarn 11 is bared when the core yarn is pulled to the longitudinal direction of the core yarn 12 strongly, so that the strength of the elastic yarn 11 is related to the single yarn strength used as the core yarn.

[0093] Consequently, the core yarn 12 which the durability to the friction is high and the fiber bundle 5 that is the covering fiber is the short fiber, can be produced in high speed by the spinning.

[0094] Next, the structure of the elastic yarn supply device 10 part will be described.

[0095] As illustrated in FIG. 4, the funnel part 60 is disposed such as to be easy to suck the end part of the elastic yarn 11 in operating manually. The air sucker device 58 for air threading is fixed below the funnel part 60. Moreover, the clamp cutter device 33 is disposed below (the down stream side of) the air sucker device 58.

[0096] The elastic yarn detecting sensor 32 is disposed between the air sucker device 58 for air threading and the clamp cutter device 33. The elastic yarn detecting sensor 32 detects whether or not the elastic yarn 11 is clamped between the air sucker device 58 for air threading and the clamp cutter device 33 by the presence of the elastic yarn 11 in setting the yarn at the beginning.

[0097] The elastic yarn detecting sensor 32, composed by the non-contact type sensor, plays the role of preventing the attachment of the elastic yarn 11.

[0098] Moreover, the yarn presence can be detected as the elastic yarn detecting sensor 32 is existed even in the yarn stopping state. Additionally, though the elastic yarn detecting sensor 32 is disposed between the air sucker device 58 for air threading and the clamp cutter device 33 in FIG. 4, it can be disposed in any place between the rotating roller 21 and the clamp cutter device 33.

[0099] For example, the air sucker device 58 can be equipped with a plurality of the yarn threading member having the yarn threading hole whose size (the diameter) is different and disposed such that the size of the yarn threading hole is smaller to the downstream side that is the elastic yarn supply guide tube 59 side as mentioned later. Therefore, as the elastic yarn 11 is threaded by the air flown on the central axis of the yarn threading hole with letting out of the air from the interval of the yarn threading member effectively, high delivering power can be acquired by jetting the high pressured air and the elastic yarn 11 can be surely supplied to the drafting unit 6 without loosening.

[0100] The elastic yarn supply guide tube 59 is protruded as the slender tube toward the elastic yarn supplying position to the drafting unit 6 (between the middle roller 8 and the front roller 9 in the preferred embodiment of the present invention) below the clamp cutter device 33. The elastic yarn supply guide tube 59 had better stretch straight below so as not to bend the elastic yarn 11 or to stabilize the drafting magnification, considering the yarn quality.

[0101] The part of the air sucker device 58 for air threading, the clamp cutter device 33 and the elastic yarn supply guide tube 59 is stored in the turn box 52 in order to freely turn them integrally. The part of the turn box 52 can be evacuated by turning or moving right and left such that the part of the elastic yarn supply guide tube 59 does not disturb in lifting the cradle of the drafting unit 6 in relation to be able to lift the half part of the cradle supporting the top roller side of the drafting unit 6 by the operation of the lifting handle 53 for checking and mending the drafting unit 6.

[0102] The drafting magunification of the elastic yarn 11 can be given by the difference of the peripheral speed ratio between the rotating roller 21 and the yarn delivering device 14.

[0103] In other words, as the peripheral speed of the yarn delivering device 14 is increased more than the peripheral speed of the rotating roller 21, the elastic yarn 11 can be maintained to draft such as more than 4 times between the rotating roller 21 and the yarn delivering device 14 including the spinning zone.

[0104] Therefore, the spinning is implemented with wrapping the fiber bundle 5 on the periphery of the elastic yarn 11 using the vortex air current by the air spinning nozzle 86 in the state that the elastic yarn 11 is maintained in the predetermined drafting magunification.

[0105] Moreover, the elastic yarn 11 and the fiber bundle 5 are adhered to unite by that a part of the fiber bundle 5 is wrapped around the elastic yarn 11 spirally as illustrated in FIG. 5A and the fascinated part K which is partly wrapped is formed and wrapped as illustrated in FIG. 5B at the same time that the fiber bundle 5 is wrapped around the elastic yarn 11. The difference of these structures is appeared in the difference of the distance between the front roller 9 and the tip of the hollow guide shaft 80 as illustrated in FIG. 12, for example.

[0106] The bearing of the elastic yarn package 20 feeding the elastic yarn 11 is supported above the rotating roller 21 and the package 20 is rotation driven to the direction that the elastic yarn 11 is released and let out by the rotation roller 21. The tension is applied to the let-out elastic yarn 11 giving the predetermined drafting magunification by the peripheral difference applied between the rotating roller 21 and the yarn delivering device 14. The elastic yarn is spun by being introduced from the front roller 9 to the air spinning device 13 with the fiber bundle 5 after drafting the sliver 4 in the state of drafting the elastic yarn.

[0107] As the yarn defect is generated when the core yarn manufacturing device is put in action, the slub catcher 17 (FIG. 4) detects the yarn defect and transmits signal to the control unit 51. The control unit 51 received the signal cuts the yarn by operating the cutter 63, and the power to the back roller 7 of the drafting unit 6 is cut off to stop by declutching a clutch 75 and the rotation of the elastic yarn package 20 is stopped by inserting the stopper 24 of the elastic yarn supply device 10 between the rotating roller 21 and the package 20 by operating the actuator 29 through the electromagnetic valve 50. Moreover, the clamp cutter device 33 is closed by switching the electromagnetic control valve 56 in parallel to the operation of the stopper 24 and the elastic yarn 11 is clamped by the clamp cutter device 33.

[0108] Meanwhile, the fiber bundle 5 in the downstream side of the back roller 7 is torn from the back roller 7 by stopping the back roller 7 and is sucked to eliminate from a fixed suction mouth 26 (FIG. 2 and FIG. 4) together.

[0109] When the slub catcher 17 detects the yarn defect, the core yarn 12 is cut by operating the cutter 63 and the end part of the cut core yarn 12 in the winding unit 16 side is once wound around the winding package 15.

[0110] Therefore, the unit 1 requires the yarn piecing and the control unit 51 in this spinning unit 1 side transmits the yarn piecing request signal. The control unit 51 in the yarn piecing vehicle 39 side received the signal stops the vehicle 39 by moving it to the spinning unit 1 necessary for this piecing.

[0111] In FIG. 4, a slack tube 71 is disposed for securing the yarn tension by sucking the spinning side core yarn 12 to suck the sag generated in piecing when restarting the supply of the sliver 4 from the spinning side in yarn piecing. The slub catcher 17 cuts the yarn if the thin or coarse yarn is detected in checking the width of the core yarn 12.

[0112] Moreover, in FIG. 4, a yarn piecing impossibility sign 62 is the sign for passing the yarn piecing vehicle 39 to the spinning unit 1 which cannot piece and is controlled via the control unit 51 by a solenoid 65 operating the yarn piecing impossibility signal 62 and a connecting link 68. If the elastic yarn detecting sensor 32 does not detect the elastic yarn 11 when the elastic yarn 11 is not existed in the elastic yarn package 20 or when the clamp cutter sensor 33 cannot clamp the elastic yarn 11, it is protruded as illustrated in the drawings and the yarn piecing vehicle 39 is passed and the abnormality is informed to the operator. The cutter 63 is also controlled by the solenoid 65 and the connecting link 67 through the control unit 51.

[0113] Next, the operational procedure of the spinning device of the present invention will be described.

[0114] Before starting to operate the core yarn manufacturing device for the first time, the yarn end of the elastic yarn 11 which is released from the elastic yarn package 20 and hangs lower by the rotating roller 21 is put into the funnel part 60 of the air sucker device 58 for air threading manually by the operator. Next, a manual switch 55 (FIG. 2 and FIG. 3) specially provided in the path side of the turn box 52 is turned on.

[0115] The manual start signal is transmitted from the manual switch 55 to the control unit 51 and the yarn is threaded that the end part of the elastic yarn 11 is passed into the air sucker device 58 for air threading by opening the electromagnetic control valve 57 (FIG. 8) for controlling the air sucker device 58 (FIG. 4) for air threading and supplying the high pressure air by the operational signal from the control unit 51.

[0116] The tip part of the elastic yarn 11 which is threaded by sucking into the air sucker device 58 for air threading is passed through the elastic yarn detecting sensor 32 and the clamp cutter device 33 at the same time. The end part of the elastic yarn 11 is cut by the cutter and is clamped by the clamp device. That is why the preparation for the elastic yarn supply device 10 is completed.

[0117] In other words, as the manual switch 55 is turned on, the end part of the elastic yarn 11 is passed through the air sucker device 58 for air threading and the elastic yarn detecting sensor 32, and the tip is clamped by the clamp cutter device 33 and the unnecessary tip part of the elastic yarn 11 is cut.

[0118] On the other hand, the automation mechanism of the piecing after cutting the yarn when the slub is generated while driving the core yarn manufacturing device will be described.

[0119] In the preferred embodiment of the present invention as illustrated in FIG. 4, as the slub is detected by the slub catcher 17, the core yarn 12 is cut by the cutter 63, the air spinning device 13 is stopped as described above, the back roller 7 is stopped and the elastic yarn 11 is stopped with cutting and clamping the end part by the clamp cutter device 33.

[0120] The yarn piecing is started from these states, however, the control unit 51 received the signal from the slub catcher 17 transmits the signal to the control unit of the yarn piecing vehicle 39 for a start and the vehicle side control unit received the signal makes the yarn piecing vehicle 39 move to the spinning unit 1 in halt condition to the right and left direction of the paper in FIG. 1 and stop when the suction nozzle 41 is coming to the position of the spinning unit 1. When the yarn piecing vehicle 39 arrives at the spinning unit 1 in halt condition, the vehicle side control unit rotates the suction nozzle 41 by turning the cam motor M at only the predetermined angle and stops in the condition that the suction mouth is located in the vicinity of the outlet of the air spinning device 13 (above-mentioned yarn capturing position) as illustrated by the chained line in FIG. 2 or the solid line in FIG. 4. This is the preparation process of the yarn discharging spinning and the vehicle side control unit transmits the preparation completion signal to the control unit 51 in the spinning unit 1 side after completing this process.

[0121] The control unit 51 in the spinning unit 1 side received this preparation completion signal is driven by connecting the halt back roller 7 to the clutch 75 in the state that the suction nozzle 41 is located in the yarn capture position as described above (the state that the suction mouth is located in the vicinity of the outlet of the air spinning device 13) and the yarn discharging spinning is implemented that the spun yarn is produced and discharged from the sliver 4 by respectively operating the spinning nozzle 86 through a low pressure switching valve 74 and the suction flow generating nozzle 82 for discharging yarn through the switching valve 76.

[0122] Therefore, only the fiber bundle 5 is supplied from the back roller 7 of the drafting unit 6 to the air spinning device 13 through the middle roller 8 which the apron is spread over and the front roller 9 (in this stage, the elastic yarn 11 is not still supplied to the air spinning device 13), and the yarn discharging spinning is implemented in the state of the incomplete yarn without the elastic yarn 11 by the jet air from the suction flow generating nozzle 82 for discharging yarn and it is discharged from the air spinning device 13. Then, the suction nozzle 41 of the yarn piecing vehicle 39 is turned to the upper yarn capture position, and the incomplete yarn discharged from the air spinning device 13 is arranged to be sucked by the suction nozzle 41.

[0123] Then, as illustrated in FIG. 9, the spinning nozzle 86 is switched to the high pressure same as the one of the normal spinning after the low pressure is maintained in the predetermined time from starting to operate. As the fiber is controlled not to swing by the vortex air current from the spinning nozzle 86 around the tip part of the hollow guide shaft 80 by maintaining the spinning nozzle 86 in low pressure just after the start of the yarn discharging spinning, the fiber can be surely sucked into the yarn path 81 of the hollow guide shaft 80 with the suction flow by the suction flow generating nozzle 82 for discharging yarn and the success ratio of the yarn discharging spinning is improved. The switching of this low and high pressure is controlled as the control unit 51 transmits the suitable signal to a high pressure switching valve 73, the low pressure switching valve 74 as illustrated in FIG. 8.

[0124] When the yarn discharging spinning and the yarn discharging can be implemented normally here, the sensor 66 in the nozzle 41 can detect the yarn presence by the suction of the suction nozzle 41.

[0125] The above vehicle side control unit determines whether or not the yarn discharging is succeeded by monitoring the state of the sensor 66 in the suction nozzle (whether or not the spun yarn is normally discharged) in the predetermined time after starting the yarn discharging spinning. More specifically, the vehicle side control unit determines that the yarn discharging spinning is succeeded when detecting the yarn presence by the yarn discharging detecting sensor 66 in the predetermined time after transmitting the preparation completion signal to the spinning unit 1 side as described above. On the other hand, if not detecting the yarn presence in the predetermined time by the sensor 66, the control unit determines to fail the yarn discharging spinning.

[0126] If the yarn discharging spinning is determined to succeed, the vehicle side control unit turns the cam motor M more to the predetermined angle and the suction nozzle 41 is turned to the lower yarn guide position. As the suction of the suction nozzle 41 is continued in turning downward, the yarn is pulled downward with sucking from the tip of the suction nozzle 41 and the delivering power is applied to the yarn by being nipped between the rotating delivery roller and the nip roller in the yarn delivering device 14 in the process.

[0127] If the sensor 66 detects the yarn in the suction nozzle 41, it is presumed that the yarn is pulled downward normally with sucking and that the delivering power is applied to the yarn by being nipped between the delivery roller and the nip roller of the yarn delivering device 14 properly in the process. In the preferred embodiment of the present invention, the sensor 66 in the suction nozzle reconfirms the yarn presence in the nozzle 41 at the point of completing the turning to the yarn guide position of the suction nozzle 41.

[0128] When the yarn presence is confirmed by the sensor 66 in the turning the nozzle 41 below, the vehicle side control unit transmits the yarn discharging detection signal (the yarn discharging success signal) to the control unit 51 in the spinning unit 1 side. The control unit 51 received the yarn discharging detection signal recognizes that the yarn pulled by the suction nozzle 41 is nipped by the yarn delivering device 14 and the yarn delivering power is applied to the yarn.

[0129] After that, the control unit 51 starts to supply the elastic yarn 11 to the air spinning device 13 by operating the elastic yarn supply device 10 and stops the operation of the suction flow generating nozzle 82 for discharging yarn in the state of keeping the operation of the spinning nozzle 86.

[0130] More precisely, the control unit 51 transmits the signal to the electromagnetic control valve 57 for starting the suction of the air sucker device 58 for air threading in the predetermined time (time (t1) in FIG. 9) after the control unit 51 recognizes that the yarn delivering power is applied.

[0131] After the predetermined time (t2) has passed, the control unit 51 releases the clamped condition of the clamp cutter device 33 through the electromagnetic control valve 56 and the actuator 29 is operated through the electromagnetic valve 50 and the rotation of the elastic yarn package 20 is started at the almost same time. Therefore, the air sucker device 58 for air threading which is already driven sucks the elastic yarn 11 and the yarn is introduced to the air spinning device 13.

[0132] That is why both the elastic yarn (the core fiber) 11 and the fiber bundle 5 are supplied to the air spinning device 13 and the core yarn spinning is started. In other words, the normal core yarn 12 is produced in the state that the elastic yarn 11 is entered into the spun yarn (the incomplete yarn) by only the fiber bundle 5.

[0133] Additionally, when the clamp cutter device 33 is opened, the suction flow generating nozzle 82 for discharging yarn is still in operation and the core yarn 12 is produced by the yarn discharging spinning by the jet air of the nozzle 82 and the spinning nozzle 86 in this point. After that, the spinning only by the spinning nozzle 86 and the hollow guide shaft 80 (the normal spinning) is implemented by that the control unit 51 controls to stop the suction flow generating nozzle 82 for discharging yarn through the switching valve 76.

[0134] And, the yarn piecing part 40 pieces the spinning side yarn to the yarn end in the winding unit 16 side that the suction mouth 42 is sucked, so that the normal spinning and the winding operations are started.

[0135] Additionally, the unnecessary parts of the yarn (the incomplete part without the elastic yarn 11 and the core yarn 12 part produced by the yarn discharging spinning by the air jet from the two nozzles 82, 86) are all sucked and eliminated into the suction nozzle 41, which is cut by the cutter not shown in the drawings of the yarn piecing part 40 during the yarn piecing operation.

[0136] As illustrated in the timing chart of FIG. 9, the above yarn piecing movement described above by the yarn piecing part 40 is implemented after supplying the elastic yarn 11 and switching to the normal spinning only by the spinning nozzle 86 by stopping the jet air of the suction flow generating nozzle 82 for discharging yarn. Accordingly, at the point that the yarn piecing part 40 actually implements the yarn piecing operation, the elastic yarn 11 is entered in it and the core yarn 12 produced by the normal spinning only by the spinning nozzle 86 arrives at the yarn piecing part 40, so that only the core yarn made by the above normal spinning is wound around the package 15.

[0137] As described above, in the preferred embodiment of the present invention, after the vehicle side control unit receives the yarn detection signal of the sensor 66 in the suction nozzle and the control unit 51 in the spinning unit 1 side receives the yarn delivering detection signal of the vehicle side control unit which is transmitted based on the yarn detection signal and it determines that the delivering power is applied to the incomplete yarn by the yarn delivering device 14, the air sucker device 58 is operated and the start of supplying the elastic yarn 11 is controlled. Accordingly, the elastic yarn is started to supply after confirming the state that the strong delivering power is applied to the yarn discharged from the air spinning device 13 (the yarn drawn by the suction nozzle 41) by the yarn delivering device 14.

[0138] It means to take the process that the delivering power is applied to the downstream in advance by the yarn delivering device 14 from the step of the incomplete yarn without the elastic yarn 11 and after that, the elastic yarn 11 is entered into the yarn.

[0139] Therefore, the shrinkable elastic yarn 11 can be surely introduced into the fiber bundle 5 and can be sent to the yarn piecing part 40 side in the downstream with taking into the fiber bundle 5, so that it demonstrates the advantages of the certainty and the stability of the yarn piecing operation.

[0140] In other words, the elastic yarn 11 can be surely threaded to the air spinning device 13 by traveling the normal fiber bundle 5 (the yarn). More specifically, the high stretchy and shrinkable elastic yarn 11 does not jam into the air spinning device 13.

[0141] In the preferred embodiment of the present invention, the control unit 51 determines (detects), so-called indirectly, that the delivering power is normally applied to the yarn by the yarn delivering device 14 with detecting the yarn presence by the sensor 66 in the nozzle 41 after turning the suction nozzle 41 downward. In other words, the sensor 66 comprising the detecting part has a role of the detector for detecting to discharge yarn normally by using the suction flow generating nozzle 82 for discharging yarn as well as a role of the detector for detecting that the delivering power is applied to the yarn by the yarn delivering device 14.

[0142] The vehicle side control unit which determines to fail the yarn discharging in the determination operation transmits the yarn delivering failure signal to the control unit 51 in the spinning unit 1 side. In such a case, as it resumes to generate the abnormality such that the fiber bundle 5 is run out, the control unit 51 received the yarn delivering signal stops the back roller 7 by declutching the clutch 75 immediately and also stops to supply the sliver 4 (the fiber bundle) to the air spinning device 13. Additionally, it is desirable to stop the operation of the spinning nozzle 86 and the suction flow generating nozzle 82 for discharging yarn. The winding of the sliver 4 to the front top roller is controlled and the damage of the front top roller can be prevented by stopping to supply the sliver 4 immediately like this. After controlling as described above, the control unit 51 informs the abnormality to the operator by the yarn piecing impossibility sign 62 etc.

[0143] The yarn piecing and the restart of the operation after the yarn is cut by generating the slub is implemented automatically, however the following variation is also considered as the control structure of the automatic yarn piecing movement. In other words, it is the structure that the same injection movement of the elastic yarn 11 is implemented as described above by regarding that the yarn is nipped between the delivery roller and the nip roller of the yarn delivering device 14 by turning it down in spite of the result of the sensor 66 in the suction nozzle at the point as the sensor 66 in the suction nozzle 41 detects the suction of the yarn (the yarn presence) when the suction nozzle 41 is turning up and after that the suction nozzle 41 turns downward. More specifically, the confirmation of the yarn presence is abbreviated in the nozzle 41 by the sensor 66 after the suction nozzle 41 turns downward.

[0144] Alternatively, the sensor 66 in the suction nozzle 41 detects the yarn sucked into the suction nozzle 41, or a special sensor can detect that the yarn is nipped between the delivery roller and the nip roller of the yarn delivering device 14 (in other words, the delivering power is applied) by providing the special sensor in the vicinity of the yarn delivering device 14. In this case, the detecting part is composed by two sensors. Moreover, it is composed only by the sensor for detecting that the yarn is nipped between the both rollers of the yarn delivering device 14.

[0145] Or, as the vehicle side control unit detects the yarn presence by the sensor 66 in the suction nozzle 41 and also detects that the yarn discharging spinning is normally implemented when the suction nozzle 41 is located in the yarn capturing position, the yarn discharging detection signal can be transmitted to the control unit 51 in the spinning unit 1 side before turning the suction nozzle 41 downward, and the control unit 51 operates the elastic yarn supply device 10 immediately after receiving the yarn discharging detection signal.

[0146] In this case, even before the delivering power is applied by the yarn delivering device 14, the delivering power by the suction power of the suction nozzle 41 is applied to the yarn discharged from the air spinning device 13. That is why the yarn is surely threaded though the elastic yarn has the characteristics of the high stretchy and being shrinkable as the elastic yarn is passed into the air spinning device 13 with the traveling of the normal fiber bundle (yarn) by starting to supply the elastic yarn after confirming that the yarn discharging spinning is normally implemented.

[0147] Besides, while the complete core yarn 12 with the elastic yarn 11 is sucked into the suction nozzle 41, the yarn is pieced by turning the suction nozzle 41 downward and pulling the yarn to the downstream. It is especially effective in the case that the suction nozzle 41 has the suction power only for pulling the yarn 12 with the shrinkable elastic yarn 11 to the downstream side with surely sucking by turning downward.

[0148] However, it is preferable that the elastic yarn 11 is started to supply after confirming to apply the strong delivering power to the yarn by detecting that the yarn is nipped by the yarn delivering device 14 (regarding that it is nipped) after the suction nozzle 41 is turned downward from the view that the yarn discharging and the yarn piecing of the core yarn whose core fiber is the elastic yarn 11 are more surely implemented. It is because that the delivering power to be nipped and sent by the yarn delivering device 14 is stronger than the delivering power by the suction flow of the suction nozzle 41.

[0149] The elastic yarn detecting sensor 32 is for detecting the presence of the elastic yarn 11 in the position between the rotating roller 21 and the clamp cutter device 33 in the elastic yarn supply device 10 part. Without the elastic yarn 11, the sensor 32 detecting it transmits the signal to the control unit 51, and the control unit 51 determines the situation such that the elastic yarn 11 is run out and the spinning operation is stopped.

[0150] Further, in this case, the above yarn piecing vehicle 39 is passed and the control for generating alarm is implemented to the operator by the display such as the yarn piecing impossibility sign 62 as illustrated in FIG. 4 without piecing the yarn by the yarn piecing vehicle 39.

[0151] Moreover, when the core yarn 12 is fully wound around the winding unit 16 and the bobbin is doffed, the stopper 24 is turned by supplying high pressure air from the cradle electromagnetic control valve 50 to the actuator 29 by the signal from the control unit 51 as illustrated in FIG. 4, the supply of the elastic yarn 11 is stopped by floating the elastic yarn package 20 and the core yarn 12 is cut by the cutter 63 disposed in the upper part of a yarn tension sensor 64 as illustrated in FIG. 4 at the same time.

[0152] Next, the deformative embodiment of the drive structure of the elastic yarn package 20 will be described.

[0153]FIG. 11 illustrates the structure in case that the part of the mechanism for controlling the rotation of the elastic yarn package 20 by turning the stopper 24 with the actuator 29 in FIG. 4 is controlled by a feed motor Mo. The drive of the rotating roller 21 is driven controlled respectively by the feed motor Mo in the respective spinning units 1, and the elastic yarn package 20 can always contact to the rotating roller 21.

[0154] The control unit 51 can control the feed motor Mo and the drafting magnification of the elastic yarn can be changed by the rotation of the elastic yarn package 20 according to the different rotation number of the respective spinning units 1. Accordingly, multiple kinds of the core yarn whose yarn qualities are different can be manufactured in one manufacturing device.

[0155] Moreover, every spinning unit 1 can drive the elastic yarn package 20 independently by the single spindle drive using the feed motor Mo. Accordingly, if the elastic yarn 11 is wound around the rotating roller 21 part for example, it also has the advantages that only one unit can be fixed by stopping the rotation of only the rotating roller 21 and the yarn can be eliminated quickly.

[0156]FIG. 10 illustrates the characteristics of the drafting magnification and the yarn strength of the elastic yarn 11 that is the core fiber in the core yarn produced by the ring spinning machine, the core yarn manufactured by the conventional spinning method and device using the covering fiber as the staple fiber and the core yarn manufactured by the manufacturing method of the present invention using the cotton 100% covering fiber.

[0157] According to FIG. 10, the yarn strength of the spun yarn using the 100% cotton covering yarn is weaker than the other spun yarn if the drafting magnification is under 4 times. However, when the drafting magnification is raised, the yarn strength is gained prominently on reaching about 4 times of the drafting magnification.

[0158] The single yarn strength depends on the core fiber strength and the strength of uniting the covering fiber, and as illustrated in the lower part of FIG. 10, the surrounding covering fiber (cotton 100%) wrapped around the elastic yarn 11 is small in area and the bonding is weak since the cross section area of the elastic yarn 11 is larger as the elastic yarn 11 is not fully pulled and therefore the occupying ratio of the surrounding covering fiber is low in the cross section of the core yarn 12 in case of the low drafting magnification, for the cross section area of the elastic yarn 11 becomes smaller in area when the elastic yarn 11 is spun in pulling condition and it is considered that the strong unite is acquired and the strength is much stronger as the ratio of the wrapped covering fiber is high.

[0159] Moreover, the yarn strength of the core yarn 12 of the present invention is transited in flat when the drafting magnification becomes about 5 times. As illustrated in the lower part of FIG. 10, it is considered that the change of the cross section area (diameter) of the elastic yarn 11 is smaller according to that the magnification becomes high even if the drafting magnification is high and the change of the wrapping fiber volume also becomes small. Consequently, considering the result and the limit of the tension breaking strength of the elastic yarn 11 itself, the drafting magnification of the elastic yarn 11 is preferable to be 4˜6 times in 40 deniers (unit for showing the yarn thickness), 4.5˜7 times in 105 deniers and 5˜8 times in 140 deniers.

[0160] Accordingly, the manufacturing method of the present invention can not only make the covering of the fiber bundle 5 to the elastic yarn 11 improve, but also can make the strength of the spun yarn using the cotton 100% covering fiber close to the yarn strength of the other spun yarn.

[0161] Further, as the elastic yarn 11 is drafted and spun as described above, the enough flexibility can be acquired and the longer core yarn than the normal elastic yarn can be acquired. In other words, the core yarn produced per unit weight of the elastic yarn 11 can be longer. Moreover, more than 10 times of the high speed spinning is available as described in the Japanese patent No. 2703189, compared with the ring spinning machine.

[0162] Moreover, when the yarn end of the core yarn produced by pulling the elastic yarn 11 in the multiple times of the drafting magnification is cut in the ring spinning machine if the core yarn is used in the loom and sewing machine etc., the elastic yarn 11 is shortened to the core yarn longitudinal direction for shrinking and the part without the elastic fiber 11 that is the core fiber is generated by just the shrunken part as the bonding with the surrounding covering fiber is weak. Accordingly, considering the shrunken part of the elastic yarn 11, the longer core yarn than the necessary core yarn for the loom and sewing machine is prepared actually and the margin to seam is necessary for the length, especially in the sewing movement based on this.

[0163] However, as the core yarn of the present invention, produced by pulling the elastic yarn 11 in the multiple times of the drafting magnification, is united with the surrounding covering fiber strongly even if the yarn end is cut, the shrinkage of the elastic yarn 11 is controlled by the covering fiber and the degree to shrink to the core yarn longitudinal direction can be small. Accordingly, the cost of the material for the elastic yarn 11 can be reduced as the marginal core yarn is reduced and there is no need to prepare the margin to seam in the sewing movement, unlike the core yarn produced by the ring spinning machine.

[0164] Due to the arrangement as describe above, the present invention demonstrates the following advantages.

[0165] According to the invention as claimed in claim 1, the excellent covering and the high durability to the friction can prevent the elastic yarn from exposing by being apart from the surrounding fiber with the strong tension.

[0166] According to the invention as claimed in claim 2, the core yarn excels in the covering and the durability to the friction, and the single yarn strength of the core yarn can be much stronger.

[0167] According to the invention as claimed in claim 3, the problem is improved that the core yarn produced by the conventional ring spinning machine is separated into the fiber bundle and the elastic yarn made from the cotton to slip. In other words, the core yarn whose yarn strength is high that the core fiber with no twist is stable in the center and the covering of the covering fiber bundle (cotton) for wrapping around the periphery is improved can be acquired. Further, as the elastic yarn that is the core fiber is spun in the elongated state, the produced core yarn can acquire the enough flexibility.

[0168] According to the invention as claimed in claim 4, as the covering fiber is wrapped around the other covering fiber, the core yarn can be acquired that high durability is demonstrated to the friction along the longitudinal direction.

[0169] According to the invention as claimed in claim 5, it becomes easier to manufacture the core yarn with high yarn strength, high covering and the high durability to the friction in high speed. Further, the longer core yarn than the length of the normal elastic yarn can be acquired. In other words, the length of the core yarn produced per unit weight of the elastic yarn can be longer, so that the cost of the material for the elastic yarn can be reduced.

[0170] According to the invention as claimed in claim 6, after confirming the yarn presence in the drawing device, the elastic yarn can start to supply to the fiber bundle. In other words, after confirming that the fiber bundle discharged from the drafting unit is discharged from the air spinning device as the normal spun yarn in starting the spinning, the elastic yarn can start to supply to the fiber bundle.

[0171] As the elastic yarn is converged into the fiber bundle (spun yarn) in the state of being normally running through the air spinning device like this, even the elastic yarn with high flexibility passes the air spinning device by riding on the running of the fiber bundle (spun yarn). Accordingly, the elastic yarn can be surely prevented from jamming in the air spinning device and the complete automation of the yarn discharging and the yarn piecing of the core yarn using the elastic yarn as the core fiber can be realized.

[0172] Moreover, as the elastic yarn is converged into the fiber bundle (spun yarn) after confirming that it runs normally through the air spinning device, the elastic yarn can be prevented from supplying in the state that the fiber bundle is failed to discharge (the spun yarn is made from the fiber bundle and is discharged from the air spinning device).

[0173] Accordingly, it can be prevented that only the elastic yarn is introduced into the yarn piecing device by extruding it with the extruding device and is pieced to the winding side core yarn. More specifically, only the elastic yarn part can be prevented from mixing into the winding package.

[0174] Further, if the detecting device does not detect the spun yarn in the predetermined time from the start to drive the drafting unit (the back roller), the fiber bundle which is supplied consecutively can be prevented from winding to the drafting roller (the front roller) by stopping the drafting unit (the back roller) immediately without supplying the elastic yarn. Therefore, the recovery work can be done in short time and the drafting roller can be prevented from damaging.

[0175] According to the invention as claimed in claim 7, after the delivering power is applied to the yarn discharged from the air spinning device, the elastic yarn can be started to supply to the fiber bundle. More precisely, the elastic yarn can be started to supply to the fiber bundle after confirming that the fiber bundle coming out of the drafting unit is discharged from the air spinning device as the normal spun yarn and the yarn delivering device has applied the strong delivering power to the spun yarn in the start of the spinning.

[0176] As the yarn delivering device is activated to the spun yarn discharged from the air spinning device and the elastic yarn is converged in the state that the strong delivering power is applied to the spun yarn by the yarn delivering device, even the high flexibility yarn can surely pass the air spinning device with the running of the fiber bundle (the spun yarn).

[0177] Accordingly, the elastic yarn can be surely prevented form jamming into the air spinning device and the core yarn using the elastic yarn as the core fiber can be surely discharged and pieced automatically.

[0178] Moreover, as the fiber bundle (the spun yarn) is running normally through the air spinning device and the elastic yarn is converged into the spun yarn after applying the delivering power by the yarn delivering device, the elastic yarn can be prevented from supplying in the state that the fiber bundle is failed to discharge (the spun yarn is made from the fiber bundle and is discharged from the air spinning device).

[0179] Accordingly, it can be prevented that only the elastic yarn is introduced into the yarn piecing device by extruding it with the extruding device and is pieced to the winding side core yarn. More specifically, only the elastic yarn part can be prevented from mixing into the winding package.

[0180] According to the invention as claimed in claim 8, the spun yarn which is made from only the fiber bundle or includes even the elastic yarn can be easily extruded for piecing yarn by moving the suction tube, and the detecting part can easily and surely detect the state that the spun yarn is extruded properly.

[0181] According to the invention as claimed in claim 9, as the air sucker device for air threading is operated first before the clamp cutter device releases to clamp it, the sag of the elastic yarn can be prevented in starting to supply and the trouble such that the elastic yarn is wound around the rotary roller etc. can be prevented.

[0182] According to the invention as claimed in claim 10, as the elastic yarn is started to supply after operating the air sucker device for air threading first, the elastic yarn can be surely supplied to the clamp cutter device and the converging route (the front roller 9 in the above preferred embodiment) with the fiber bundle without sagging the elastic yarn.

[0183] According to the invention as claimed in claim 11, the core yarn with high covering and high durability to the friction can be manufactured in high speed. Especially, it is effective to use such as the 100% cotton short fiber as the covering fiber that is the fiber bundle. 

1. A core yarn that a fiber bundle made from a short fiber covers an elastic yarn used as a core fiber, wherein the power necessary for breaking the fiber bundle in slipping the fiber bundle on the elastic yarn when pulling to the longitudinal direction is stronger than the power necessary for breaking the whole yarn when pulling to the longitudinal direction.
 2. A core yarn that a fiber bundle made from a short fiber covers an elastic yarn used as a core fiber, wherein the fiber bundle covers the core fiber made by centralizing the elastic yarn and the fascinated part that a part of the fiber bundle is wrapped around the elastic yarn is provided in the covering of the fiber bundle around the elastic yarn.
 3. A core yarn that a fiber bundle made from a short fiber covers an elastic yarn used as a core fiber, wherein the elastic yarn used as a core fiber is drafted in more than 4 times of the drafting magnification between an elastic yarn supply device and a yarn delivering device disposed in the downstream side of a spinning device which is equipped with an air spinning nozzle for generating the vortex air spinning and a hollow guide shaft for implementing air spinning by the vortex air current and the fiber bundle covers the core fiber made by centralizing the elastic yarn.
 4. A core yarn that a fiber bundle made from a short fiber covers an elastic yarn used as a core fiber, wherein the elastic yarn is disposed in the central part and is parallel to the longitudinal direction, it is composed that one end side is located in the central part of the core yarn with heading in almost parallel to the longitudinal direction and the other end is exposed in the outer surface of the core yarn spirally in each fiber comprising the fiber bundle for covering and the fiber bundle for covering has the consecutive structure that the other end side of the respective fibers is wrapped around the trailing other fiber and the other end side of the other fiber is also wrapped around the other trailing fiber.
 5. A core yarn manufacturing method characterized in that, providing an elastic yarn supply device and a spinning device for implementing air spinning by the vortex air current equipped with an air spinning nozzle for generating the vortex air current and a hollow guide shaft, the elastic fiber used as the core fiber is drafted in more than 4 times of the drafting magnification between the elastic yarn supply device and a yarn delivering device disposed in the downstream side of the spinning device, and the elastic fiber and the fiber bundle are supplied to the hollow guide shaft by the spinning device with drafting and the fiber made from the short fiber comprising the fiber bundle covers the elastic yarn.
 6. A core yarn manufacturing device, comprising: a drafting unit for drafting a fiber bundle; an elastic yarn supply device for supplying an elastic yarn used as a core fiber to the fiber bundle; an air spinning device for producing a core yarn by introducing the elastic yarn and the fiber bundle and activating the vortex air current on it; a yarn delivering device disposed in the downstream side of the air spinning device; a winding unit for winding the core yarn discharged from the yarn delivering device; and a yarn piecing device for piecing the core yarn in the spinning side and the core yarn in the winding side, wherein an extruding device for introducing yarn discharged from the air spinning device to the yarn piecing device by extruding it, a detecting device for detecting the yarn presence in the extruding device and a control unit for controlling the supply of the elastic yarn by the elastic yarn supply device based on the result of the detecting device are provided.
 7. A core yarn manufacturing device, comprising: a drafting unit for drafting a fiber bundle; an elastic yarn supply device for supplying an elastic yarn used as a core fiber to the fiber bundle; an air spinning device for producing a core yarn by introducing the elastic yarn and the fiber bundle and activating the vortex air current on it; a yarn delivering device disposed in the downstream side of the air spinning device; a winding unit for winding the core yarn discharged from the yarn delivering device; and a yarn piecing device for piecing the core yarn in the piecing side and the core yarn in the winding side, wherein an extruding device for introducing the yarn discharged from the air spinning device to the yarn piecing device by extruding it, a detecting device for detecting that the delivering power by the yarn delivering device is applied to the yarn extruded by the extruding device and a control unit for controlling the supply of the elastic yarn by the elastic yarn supply device based on the result of the detecting device are provided.
 8. A core yarn manufacturing device as claimed in claim 6 or claim 7, wherein the extruding device is a movable suction tube and the detecting device detects the yarn presence in the suction path of the suction tube.
 9. A core yarn manufacturing device as claimed in any one of claim 6 to claim 8, wherein the elastic yarn supply device has an air sucker device and a clamp cutter device, and the control unit controls to release the clamp of the elastic yarn by the clamp cutter device after the predetermined time since the air sucker device is operated in starting to supply the elastic yarn.
 10. A core yarn manufacturing device as claimed in claim 9, wherein the elastic yarn supply device has a supply roller which is rotated in contact with a yarn feeding package of the elastic yarn and the control unit controls to start to supply the elastic yarn by the supply roller and to release the clamp of the elastic yarn by the clamp cutter at almost the same time when starting to supply the elastic yarn.
 11. A core yarn manufacturing device as claimed in any one of claim 6 to claim 10, wherein the air spinning device has a hollow guide shaft and a nozzle member for generating the vortex air current in the tip part of the hollow guide shaft, and the core yarn is produced by activating the vortex air current using the nozzle with supplying the elastic yarn and the fiber bundle from the tip side to the yarn path of the guide shaft. 